The Spread Differential tries to measure the speed of the market in any given direction. The histogram plots levels above or below zero in a sequence of Humps and Waves. Humps are repetitions of the previous trend before dropping to or near 0 whilst Waves are similar to Humps but the histogram must drop to or near 0 prior to forming another wave. You might notice that in no trend does the indicator ever form more than 2 waves. The indicator should be used in conjunction with the MA's selected in the panel to identify possible points of failure.